/*-------------------------------------------------------------------------
-
_divsint.c :- routine for signed int (16 bit) division. just calls
routine for unsigned division after sign adjustment
Written By - Sandeep Dutta . sandeep.dutta@usa.net (1999)
- This program is free software; you can redistribute it and/or modify it
- under the terms of the GNU General Public License as published by the
+ This library is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Library General Public License as published by the
Free Software Foundation; either version 2, or (at your option) any
later version.
-
- This program is distributed in the hope that it will be useful,
+
+ This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- GNU General Public License for more details.
-
- You should have received a copy of the GNU General Public License
+ GNU Library General Public License for more details.
+
+ You should have received a copy of the GNU Library General Public License
along with this program; if not, write to the Free Software
Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
-
+
In other words, you are welcome to use, share and improve this program.
You are forbidden to forbid anyone else to use, share and improve
- what you give them. Help stamp out software-hoarding!
+ what you give them. Help stamp out software-hoarding!
-------------------------------------------------------------------------*/
-int _divsint (int a, int b)
-#ifndef SDCC_STACK_AUTO
- critical
+
+
+#include <sdcc-lib.h>
+
+#if _SDCC_MANGLES_SUPPORT_FUNS
+unsigned unsigned _divuint (unsigned x, unsigned y);
#endif
+
+/* Assembler-functions are provided for:
+ mcs51 small
+ mcs51 small stack-auto
+*/
+
+#if !defined(SDCC_USE_XSTACK) && !defined(_SDCC_NO_ASM_LIB_FUNCS)
+# if defined(SDCC_mcs51)
+# if defined(SDCC_MODEL_SMALL)
+# if defined(SDCC_STACK_AUTO) && !defined(SDCC_PARMS_IN_BANK1)
+# define _DIVSINT_ASM_SMALL_AUTO
+# else
+# define _DIVSINT_ASM_SMALL
+# endif
+# endif
+# endif
+#endif
+
+#if defined _DIVSINT_ASM_SMALL
+
+static void
+_divsint_dummy (void) __naked
+{
+ __asm
+
+ #define xl dpl
+ #define xh dph
+
+ .globl __divsint
+
+ // _divsint_PARM_2 shares the same memory with _divuint_PARM_2
+ // and is defined in _divuint.c
+#if defined(SDCC_PARMS_IN_BANK1)
+ #define yl (b1_0)
+ #define yh (b1_1)
+#else
+ #define yl (__divsint_PARM_2)
+ #define yh (__divsint_PARM_2 + 1)
+#endif
+__divsint:
+ ; xh in dph
+ ; yh in (__divsint_PARM_2 + 1)
+
+ clr F0 ; Flag 0 in PSW
+ ; available to user for general purpose
+ mov a,xh
+ jnb acc.7,a_not_negative
+
+ setb F0
+
+ clr a
+ clr c
+ subb a,xl
+ mov xl,a
+ clr a
+ subb a,xh
+ mov xh,a
+
+a_not_negative:
+
+ mov a,yh
+ jnb acc.7,b_not_negative
+
+ cpl F0
+
+ clr a
+ clr c
+ subb a,yl
+ mov yl,a
+ clr a
+ subb a,yh
+ mov yh,a
+
+b_not_negative:
+
+ lcall __divuint
+
+ jnb F0,not_negative
+
+ clr a
+ clr c
+ subb a,xl
+ mov xl,a
+ clr a
+ subb a,xh
+ mov xh,a
+
+not_negative:
+ ret
+
+ __endasm;
+}
+
+#elif defined _DIVSINT_ASM_SMALL_AUTO
+
+static void
+_divsint_dummy (void) __naked
{
- register int r;
-
- r = _divuint((a < 0 ? -a : a),
- (b < 0 ? -b : b));
- if ( (a < 0) ^ (b < 0)) {
-
- return -r;
- }
- else {
-
- return r;
- }
+ __asm
+
+ #define xl dpl
+ #define xh dph
+
+ .globl __divsint
+
+__divsint:
+
+ clr F0 ; Flag 0 in PSW
+ ; available to user for general purpose
+ mov a,xh
+ jnb acc.7,a_not_negative
+
+ setb F0
+
+ clr a
+ clr c
+ subb a,xl
+ mov xl,a
+ clr a
+ subb a,xh
+ mov xh,a
+
+a_not_negative:
+
+ mov a,sp
+ add a,#-2 ; 2 bytes return address
+ mov r0,a ; r0 points to yh
+ mov a,@r0 ; a = yh
+
+ jnb acc.7,b_not_negative
+
+ cpl F0
+
+ dec r0
+
+ clr a
+ clr c
+ subb a,@r0 ; yl
+ mov @r0,a
+ clr a
+ inc r0
+ subb a,@r0 ; a = yh
+
+b_not_negative:
+
+ mov r1,a ; yh
+ dec r0
+ mov a,@r0 ; yl
+ mov r0,a
+
+ lcall __divint
+
+ jnb F0,not_negative
+
+ clr a
+ clr c
+ subb a,xl
+ mov xl,a
+ clr a
+ subb a,xh
+ mov xh,a
+
+not_negative:
+ ret
+
+ __endasm;
}
+
+#else // _DIVSINT_ASM_
+
+int
+_divsint (int x, int y)
+{
+ register int r;
+
+ r = _divuint((x < 0 ? -x : x),
+ (y < 0 ? -y : y));
+ if ( (x < 0) ^ (y < 0))
+ return -r;
+ else
+ return r;
+}
+
+#endif // _DIVSINT_ASM_
projects / fw / sdcc / blobdiff